I have a 2002 A6 Avant that has an alarm that goes off for no reason. I installed a motion detector button so I can disarm the motion detector, but it still goes off sometimes.

I don't care to have an alarm. Can I disconnect the alarm somehow by unplugging a harness plug from the Comfort Control Module? If so, which one? Would disconnecting the alarm turn off any other functions?

If the Comfort Control Module (4B0962258C) was faulty, shouldn't other issues occur with interior lights and door locks? The only other electrical issue with the car is the default temp unit is C rather than F and must be changed every time the car is started. I haven't checked yet if the CCM has had water in it or if the battery drain holes are plugged.

Does anybody have a photo of the Comfort Control Module mouting location under the carpet?

 

Do you have access to a vag-com? It will be able to tell you why the alarm is going off. That might help you diagnose the issue. My GUESS, and only a GUESS, is the drivers door latch is failing. Common issue, when it fails it can either tell the car your door is open when it's closed, or tell your car the door is closed when it is open. Besides some other weird things.

I'm basing this off if your have deactivated the motion sensor using the button on the B pillar then the only other thing that can set off the alarm is the opening of a door/hood/boot. Now of course this is assuming the alarm actually works as it's suppose to.

This is why a vag-com is usefull. It will tell you exaclty why the alarm was triggered. IE:

8 Faults Found:
01371 - Alarm triggered by Door Contact Switch: Driver's Side
35-00 - -
01572 - Alarm triggered by Door Contact Switch: Passenger Side
35-00 - -
01374 - Alarm triggered by Terminal 15
35-00 - -
01370 - Alarm triggered by Interior Monitoring
35-00 - -
01368 - Alarm triggered by Luggage Compartment Switch
35-00 - -
01134 - Alarm Horn (H12)
49-00 - No Communications
01134 - Alarm Horn (H12)
76-00 - Terminal 30 missing
01134 - Alarm Horn (H12)
77-00 - Internal Supply Voltage

 

I don't have VAG-COM.

I can buy the cable and software from Ross-Tech for about $250
Ross-Tech Store: VCDS License with KII-USB Interface

Or I can buy the ISO 9141 cable and driver by itself from ebay for about $9
VAG-COM USB KKL 409.1 OBD2 OBDII Cable Scanner ISO9141 for AUDI Volkswagen Skoda | eBay

Ross-Tech offers some downloads for 3rd party ISO cables.
Ross-Tech: VCDS: Downloads: Which One?

This is a table of functions:
Ross-Tech: VCDS: Function Table

Based on the table, I'm guessing I can get by with the $9 ebay cable and driver. Is that right?

 

yep, the cheap cable is just fine.

 

with the motion detector off, my alarm has been going off again the last few days. The interior monitoring did not have any fault codes but the Central Lock/Alarm D35 did:

VAG Number: 4B0 962 258 J
Component: Central Lock/Alarm D35
1 Fault Found:
01370 - Alarm triggered by Interior Monitoring
35-00

What does this mean?

 

Are disabling the interior motion sensor EACH time you lock the car? The car alarm re enables the motion sensor every time the car is locked unless you press the button.

you can also turn the sensitivity of the motion sensors down with the vag-com. Do a search for adjusting interior motion sensors and vag-com.

If none of that works, it could be a bad ultrasonic motion sensor or maybe a bad wire.

 

I press the button every time and it lights up.

 

I followed the instructions below and changed the setting to 50. I'm guessing the lower the value the lower the sensitivity. Is there a way to just turn it off permanently?

Adjusting sensitivity of ultrasonics
1) Select Control Module
2) Select 45 - Int. Monitor
3) Under Advanced Functions, select "Adaptation - 10"
4) Read channel 01
5) enter a value between 50-100 (it should be 100 by default) for the sensitivity of the ultra-sound sensors
6) Save.

 

I don't know if you can completely disable it. IIRC you can't, but I am not sure. I know that a setting of 50 pretty much turns it off. You have to practically bang the sensor with your hand to get it to detect the motion. I wonder if you can test the motion sensors. I'm not sure how people come to the conclusion they are bad.

 

where is the actual motion detector at?